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In X-ray grating-based phase contrast imaging, information retrieval is necessary for quantitative research, especially for phase tomography. However, numerous and repetitive processes have to be performed for tomographic reconstruction. In this paper, we report a novel information retrieval method, which enables retrieving phase and absorption information by means of a linear combination of two mutually conjugate images. Thanks to the distributive law of the multiplication as well as the commutative law and associative law of the addition, the information retrieval can be performed after tomographic reconstruction, thus simplifying the information retrieval procedure dramatically. The theoretical model of this method is established in both parallel beam geometry for Talbot interferometer and fan beam geometry for Talbot-Lau interferometer. Numerical experiments are also performed to confirm the feasibility and validity of the proposed method. In addition, we discuss its possibility in cone beam geometry and its advantages compared with other methods. Moreover, this method can also be employed in other differential phase contrast imaging methods, such as diffraction enhanced imaging, non-interferometric imaging, and edge illumination. [ABSTRACT FROM AUTHOR]

Purpose The dent is one of typical surface defects on the surfaces of the machine elements and it is not in fact inerratic. This work aims to investigate the effect of a single dent with a marginal bump on the film shape in elastohydrodynamic lubrication (EHL) point contacts.Design/methodology/approach The experimental investigations of a single dent with marginal bump were carried out using multi-beam interferometry in EHL point contacts. In the meantime, its numerical simulation was also finished using multi-level method and multilevel multi-integration method. The effects of the entrainment velocity and the applied load as well as the slide-roll ratio on the film were chiefly discussed. Meanwhile, the comparison of films between smooth and dented surfaces was conducted under simple sliding conditions.Findings Under pure sliding conditions, the minimum film thickness presents itself near the marginal bump at lower entrainment velocity. The inlet dimple before the marginal bump is subjected to the operating conditions. Under pure rolling conditions, the shape of the dent is almost unchanged when it is passing through the contact region at lower entrainment velocity. The dent depth hardly depends on the applied load under static conditions. However, larger load enhances the inlet dimple and the elastic deformation of the dent with the marginal bump under pure sliding conditions.Originality/value This work is helpful to understanding the effect of the marginal bump before the single dent on point contact EHL films. [ABSTRACT FROM AUTHOR]

Objective: To explore the diagnosis and treatment of head and neck Castleman's disease (CD), and to improve the understanding of the disease. Methods: The clinical data of 41 patients with head and neck CD treated from January 2007 to July 2017 in the First Affiliated Hospital of Zhengzhou University were analyzed retrospectively. The patients were divided into two groups: localized CD (LCD, n =27) and multicentric CD (MCD, n =14). The clinical manifestations, laboratory examinations, operations, pathological findings and follow-up data were analyzed. Results: LCD was characterized by asymptomatic enlargement of the single lymph node with mild clinical symptoms. The main pathological type was hyaline vascular type, which can be cured by surgical treatment. MCD accompanied by fever 9 cases(64.3%), anemia 8 cases (57.1%), splenomegaly 7 cases (50.0%), respiratory symptoms 6 cases (42.9%), with multiple enlarged superficial and deep lymph nodes with pain, pleural effusion, and edema of lower extremity, C-reaction protein increased in 8 cases (57.1%), hypoproteinemia 8 cases(57.1%), globulin increased 7 cases (50.0%) and neutropenia 6 cases(42.9%). The main pathological type was plasma cell type in 7 cases (50.0%), and also there were 4 cases of hyaline vascular type and 2 cases of mixed type. Chemotherapy with or without rituximab was the main treatment. Most patients received complete or partial remission except for 2 patients who died of lung infection due to chemotherapy. Conclusions: The diagnosis of head and neck CD depends on pathological examination. LCD shows mild symptoms and good prognosis after surgery. However, clinical manifestations of MCD are complex, with relatively poor prognosis after comprehensive treatment.